On the main screen, Click on the “Extensions” link on the left side of the window as shown below:

On the next screen , to add sip device select “Generic SIP Device” from the drop-down menu and click submit as shown below:

On next screen, enter the extension number you want to assign to this SIP device in the “User Extension” field, and the display name in the “Display Name” field, as shown below:

Now scroll down to the “Device Options” section and enter the password for this SIP device in the “Secret” field as shown below.

Scroll down to the “Fax Handling” section and select “disabled” from the drop-down menu for the “Fax Extension” field as shown below:

Scroll down further to the “Recording Options” section, select “Never” for both recording options, select “Dislabled” for the “Status” field in the “Voicemail & Directory” section, and click the submit button to save changes as show below:

After clicking on submit you will notice an orange link which says “Apply Configuration changes”. Click on this link to save the new user you just created in the asterisk configuration files. The new user will not be created inside asterisk until you apply the configuration changes by clicking on this link as shown below:

After clicking the apply configuration link, another dialogue box will open to confirm and save application changes, as shown below. Click “Continue with reload” link to save changes: